The present invention relates to a processing apparatus and method, and more particularly to a processing apparatus and method for transferring a pattern of a mold as an original to a plate, such as a wafer. The present invention is particularly suitable for a processing apparatus that utilizes the nanoimprint technology as fine processing to manufacture a semiconductor, a Micro Electro-Mechanical Systems (“MEMS”), etc.
The nanoimprint lithography has already been known as one alternative technology to the photolithography that uses the ultraviolet (“UV”) light, X-rays and electron beams to form a fine pattern for a semiconductor device. The nanoimprint lithography is a technology that transfers a pattern to a resist by pressing a model or mold having a fine pattern against a substrate, such as a wafer, to which a resinous material or the resist is applied.
The nanoimprint has several types, and one method is a photo-curing method. See, for example, M. Colburn et al., “Step and Flash Imprint Lithography: A New Approach to High-Resolution Patterning”, Proceedings of the SPIE's 24th International Symposium on Microlithography: Emerging Lithographic Technologies III, Santa Clara, Calif., Vol. 3676, Part One, pp. 379-389, March 1999. The photo-curing method is a method of exposing and curing the UV curable resin as the resist while pressing a transparent mold against it, and of releasing the mold.
FIG. 15 is a sectional view showing a relationship among a conventional mold M, a mold chuck 11, and a mold chuck stage 12. The mold M has a relief pattern P on its surface, and is fixed onto the mold chuck 11 by a mechanical member (not shown). 11P denote plural positioning pins for restricting a position of the mold M on the mold chuck 11 in installing the mold M on the mold chuck 11. The mold chuck 11 is also placed on the mold chuck stage 12 by another mechanical member (not shown). The mold chuck 11 has an opening 11H and the mold chuck stage 12 has an opening 12H, and these openings 11H and 12H allow the UV light emitted from a light source (not shown) to pass through the mold M. Plural load sensors (not shown) as force detectors are attached to the mold chuck 11 or the mold chuck stage 12.
The mold M is pressed against the resist (not shown) via the mold chuck stage 12 and the mold chuck 11. During pressing, in accordance with the output of the load sensor, the mold chuck stage 12 controls an inclination of the mold chuck 11 and a servomotor (not shown) controls a compression state of the mold M. Thereafter, the UV light is irradiated onto the mold M via the openings 11H and 12H.
One proposed method assists release by utilizing the ultrasonic vibration in a pattern's depth direction during release. See, SCIVAX Corporation, 03. Imprint Technology, Sep. 7, 2005.
Other prior art include Japanese Patent Applications, Publication Nos. 2004-288811 and 2003-7597, and Japanese Patent No. 3,450,631.
FIG. 16 is a sectional view showing a compression state of the mold M having the transfer pattern P against a resist R on a wafer W. A principal releasing force after photo-curing is a force for releasing a perpendicular surface PW of the transfer patter P from a resist contact surface in parallel rather than a force for perpendicularly releasing horizontal planes of a concave PB, a convex PT, and a horizontal part PS of the transfer pattern P from the resist contact surfaces. One typical method of reducing the releasing force is a method of applying the release agent to the mold, but the durability of the release agent weakens as the release times increases, and the force necessary for the release disadvantageously increases as the release times increases.
SCIVAX Corporation, 03. Imprint Technology, Sep. 7, 2005, teaches to apply the ultrasonic vibration to the mold during release, but is silent about a detailed pressure relationship between the mold and the resist in applying the vibration. Japanese Patent Application, Publication No. 2004-288811 teaches to apply the ultrasonic vibration to the mold during transferring so as to lower the molten resin viscosity through the ultrasonic vibration, to reduce the compression force, and to shorten the transfer time, rather than facilitating the release. See, for example, Japanese Patent Application, Publication No. 2004-288811, paragraph nos. 0006 and 0007. After all, the release of the mold requires experience and skill, a long time period and/or a large force. A long release time period lowers the throughput of the processing apparatus, and a large release force needs a bulk releasing force generator, causing a large size of the entire apparatus or an increased cost.